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Science China Chemistry 2021年第7期64卷 1157-1163页

作者： Zikun Wang Linxuan LI Xueying Zhang Xihe Bi Department of Chemistry Northeast Normal UniversityChangchun 130024China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

C(CO)–alkyl bonds are ubiquitous in a variety of organic molecules,and their selective activation and functionalization are important for the reconstruction of simple ketones into valuable building blocks.However,due to the thermodynamic and kinetic stability,the cleavage and transformation of the unstrained C(CO)–alkyl bonds remain a significant challenge.Herein,we report a novel silver-catalyzed scission of the unstrained C(CO)–alkyl bond of ketones by reacting with N-isocyanoiminotriphenylphosphorane(NIITP)under mild conditions.This method could transform a variety of unstrained ketones into iminophosphoranes and nitriles in high yields.Experimental and computational studies disclosed the reaction proceeded through an unprecedented[3+2]/retro-[3+2]cycloaddition mechanism.

关键词： silver-catalyzed C-C bond scission unstrained ketones tertiary alcohol intermediates cycloaddition

Real-Time Control for CPS of Digital Airplane Assembly with Robust H-Infinity Theory

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Tsinghua Science and Technology 2015年第4期20卷 376-384页

作者： Hui li linxuan Zhang Tianyuan Xiao Jietao Dong State CIMS Engineering Research Cente at Tsinghua University

This study introduces a real-time controller design method under the effects of network time delay and external disturbance. The study first introduces the digital, virtual, intelligent trend of airplane assembly and reveals the status and problems of digital airplane assembly studies. The Cyber-Physical System （CPS） structure is then proposed for digital airplane assembly, and the real-time control issues are discussed. Then, the question of real- time control undertaken by a parallel robot is simplified to a control question with bounded time delay and complex interference, and a mathematical description is presented. Next, a robust Hoo controller with a disturbance degree of decay 7 is designed according to the mathematical description. Finally, a simulation is conducted. All of the experiment results show the feasibility of the above proposed methods.

关键词： cyber physical system network time delay robust H-infinity control linear matrix inequality

Synergic Motion Trajectory Planning for Airplane Docking Based on6PURU Parallel Mechanism

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Tsinghua Science and Technology 2015年第2期20卷 188-199页

作者： Hui li linxuan Zhang Tianyuan Xiao Jietao Dong State CIMS Engineering Research Center at Tsinghua University

Motion planning issues encountered in assembling airplanes by employing the 6PURU parallel mechanism are analyzed in this paper. A sine curve of the change rate of acceleration, which is called as jerk in the following text, is proposed for uniaxial flexible acceleration and deceleration planning based on the optimal time and velocity and acceleration constraints. Compared with other curves, the proposed curve can realize a continuous n-order derivative and the smooth change of the speed and acceleration. The method is computational^y simple and suitable for programming. In addition, a multiaxial coordinated movement scheme is proposed. The motion trajectory is no longer simply split into many single-direction trajectories nor are all single-direction planning trajectories combined directly. The multiaxial coordinated movement scheme aims to achieve synergic movement in multiple directions to ensure smoothness of the movement in the event of a kinematic error when maintaining a stable value. If the movement fails to achieve this goal, driving force mutations will deteriorate the effect of synergic movement. A physical model of the parallel mechanism is developed in simMechanics, and a holistic system model is completed in SIMUliNK. The feasibility of the new planning algorithm is simulated and tested, and then, the multiaxial synergic movement planning method is proposed and verified.

关键词： assembly simulation motion trajectory planning parallel mechanism simMechanics

Data fusion and simulation-based planning and control in cyber physical system for digital assembly of aeroplane

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International Journal of Modeling, Simulation, and Scientific Computing 2015年第3期6卷 66-84页

作者： Hui li linxuan Zhang Tianyuan Xiao Jietao Dong State CIMS Engineering Research Center at Tsinghua University Main Building Room 604 Beijing 100084P.R.China State CIMS Engineering Research Center at Tsinghua University Main Building Room 601 Beijing 100084P.R.China State CIMS Engineering Research Center at Tsinghua University Main Building Room 619 Beijing 100084P.R.China

This paper introduces a CPS application for intelligent aeroplane assembly.At first,the CPS structure is presented,which acquires the characteristics of general CPS and enables“simulation-based planning and control”to achieve high level intelligent assembly.Then the paper puts forward data fusion estimation algorithm under synchronous and asynchronous sampling,respectively.The experiment shows that global optimal distributed fusion estimation under synchronized sampling proves to be closer to the actual value compared with ordinary weighted estimation,and multi-scale distributed fusion estimation algorithm of wavelet under asynchronous sampling does not need time registration,it can also directly link to data,and the error is smaller.This paper presents hybrid control strategy under the circumstance of joint action of the inner and outer loop to address the problems caused by the less controllable feature of the parallel mechanism when undertaking online process simulation and control.A robust adaptive sliding mode controller is designed based on disturbance observer to restrain inner interference and maintain robustness.At the same time,an outer collaborative trajectory planning is also designed.All the experiment results show the feasibility of above proposed methods.

关键词： Intelligent aeroplane assembly cyber physical system multi-sensor data fusion simulation-based control disturbance observer robust adaptive sliding mode controller

A dynamic delivery strategy for material handling in mixed-model assembly lines using decentralized supermarkets

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International Journal of Modeling, Simulation, and Scientific Computing 2015年第4期6卷 73-91页

作者： Jietao Dong linxuan Zhang Tianyuan Xiao Hui li National CIMS Engineering Research Center Tsinghua University Beijing 100084 P.R.China

Material handling has become one of the major challenges in modern production management.Consequently,this paper intends to investigate the part delivery of mixedmodel assembly lines with decentralized supermarkets and tow trains.Besides,uncertain exception disturbances,including tow train failures and adjustments of the production sequence,are also considered.To solve this problem,a heuristic-based dynamic delivery strategy is proposed,which dynamically schedules the route,departure time,quantities and types of loaded parts for each tour.To evaluate the performance of this strategy,it is used to solve an instance in comparison with the periodic delivery strategy,experimental results are reported and their performances are compared under different metrics.Moreover,a multi-scenario analysis is employed to determinate the long-term decisions,including the number of tow trains and the route layout.Finally,the critical storage is suggested to be set for each station to avoid part starvation resulting from disturbances,and its effect on the delivery performance is investigated.

关键词： Mixed-model assembly lines dynamic part delivery supermarket tow train critical storage.

INS-GNSS Integrated Navigation Algorithm Based on TransGAN

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Intelligent Automation & Soft Computing 2023年第7期37卷 91-110页

作者： Wang linxuan Kong Xiangwei Xu Hongzhe li Hong Chinese Flight Test Establishment Xi’an710089China Xi’an Jiaotong University Xi’an710049China

With the rapid development of autopilot technology,a variety of engi-neering applications require higher and higher requirements for navigation and positioning accuracy,as well as the error range should reach centimeter level.Single navigation systems such as the inertial navigation system(INS)and the global navigation satellite system(GNSS)cannot meet the navigation require-ments in many cases of high mobility and complex environments.For the purpose of improving the accuracy of INS-GNSS integrated navigation system,an INS-GNSS integrated navigation algorithm based on TransGAN is proposed.First of all,the GNSS data in the actual test process is applied to establish the data set.Secondly,the generator and discriminator are constructed.Borrowing the model structure of generator transformer,the generator is constructed by multi-layer transformer encoder,which can obtain a wider data perception ability.The generator and discriminator are trained and optimized by the production countermeasure network,so as to realize the speed and position error compensa-tion of INS.Consequently,when GNSS works normally,TransGAN is trained into a high-precision prediction model using INS-GNSS data.The trained Trans-GAN model is emoloyed to compensate the speed and position errors for INS.Through the test analysis ofﬂight test data,the test results are compared with the performance of traditional multi-layer perceptron(MLP)and fuzzy wavelet neural network(WNN),demonstrating that TransGAN can effectively correct the speed and position information when GNSS is interrupted,with the high accuracy.

关键词： GNSS INS TransGAN integrated navigation

异质光照条件下克隆整合对入侵植物南美蟛蜞菊化感作用的影响

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Journal of Plant Ecology 2022年第3期15卷 663-671页

作者： Lei Pu Lang Cheng Ai li Sha liang Qing Wei Shulan Wu linxuan He Xiangning Xu Ningfei Lei Jinsong Chen College of Ecology and Environment Chengdu University of TechnologyChengdu 610059China College of life Science Sichuan Normal UniversityChengdu 610101China No.405 Geological Team Sichuan Bureau of Geology and Mineral ResourcesChengdu 610066China

植物入侵已成为全球生态系统最严重的威胁之一。当具有克隆生长能力的入侵植物入侵或定殖到新的生境时,它们相互连接的分株可能受到异质光照的影响。在异质光照条件下,克隆整合对入侵植物化感作用的影响尚不清楚。为研究异质光照条件下... 详细信息

植物入侵已成为全球生态系统最严重的威胁之一。当具有克隆生长能力的入侵植物入侵或定殖到新的生境时,它们相互连接的分株可能受到异质光照的影响。在异质光照条件下,克隆整合对入侵植物化感作用的影响尚不清楚。为研究异质光照条件下克隆整合对入侵植物南美蟛蜞菊(Wedelia trilobata)化感作用的影响,采用两个连续分株的克隆片段进行了盆栽试验。较老的分株暴露在全光下,而年轻的分株则受到20%的全光照。同时,每个克隆片段的年轻分株与目标植株(一个番茄苗)在盆栽中相邻生长。南美蟛蜞菊的两个连续分株之间的匍匐茎设置切断和不切断两种处理。另外,两株番茄幼苗(一株作为目标植株)在盆栽中相邻生长作为对照。研究结果表明,当与目标植物相邻生长的南美蟛蜞菊分株之间的匍匐茎保持完整时,目标植株的生物量积累、叶片叶绿素和氮含量、叶绿素荧光参数和净光合速率及其根长和活性相较于匍匐茎切断处理显著降低。异质光照条件下连续两个分株之间碳水化合物的运输或共享可以增强20%全光处理下年轻分株的化感作用。克隆整合在异质光照条件下对具有克隆生长能力的入侵植物的入侵或定殖具有重要意义。

关键词：匍匐茎植物克隆整合入侵机制异质环境化感作用

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论《剪灯新话》“桃源意境”特质及其成因

九江学院学报（社会科学版） 2021年第4期40卷 47-52页

作者：李琳萱宝鸡文理学院文学与新闻传播学院陕西宝鸡721000

《剪灯新话》是明初产物,作为中国古代文言小说,具有转折期的特点。同理,小说中存在的桃源叙事,亦具有转折的特性:神圣的桃源仙境与雅洁的桃源田园融合,逐渐走向富有俗尘气息的桃源生活。这种“桃源意境”现象的转变,可归因于两点:一是... 详细信息

《剪灯新话》是明初产物,作为中国古代文言小说,具有转折期的特点。同理,小说中存在的桃源叙事,亦具有转折的特性:神圣的桃源仙境与雅洁的桃源田园融合,逐渐走向富有俗尘气息的桃源生活。这种“桃源意境”现象的转变,可归因于两点:一是文本和作家所依托的明初复杂的时代特征:世俗性;二是文本背后作家“俗儒”的定性。由此“桃源意境”的叙事呈现出世俗的特性,从而反映出瞿佑对于时代的选择性。

关键词：《剪灯新话》桃源意境世俗特质俗儒

主观社会支持与自尊勾连：中国视障群体数字媒介可及性与使用态度研究

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国际新闻界 2023年第2期45卷 81-106页

作者：李彪景恬高琳轩中国人民大学新闻学院

视障者作为数字弱势群体虽受益于数字媒介，却也面临了多重复杂的不平等。本文主要关注视障群体在数字媒介使用及融入过程中，其数字媒介可及性、感知媒介歧视与数字媒介使用态度之间的关系，以刺激—机体—反应（SOR）理论为框架，构... 详细信息

视障者作为数字弱势群体虽受益于数字媒介，却也面临了多重复杂的不平等。本文主要关注视障群体在数字媒介使用及融入过程中，其数字媒介可及性、感知媒介歧视与数字媒介使用态度之间的关系，以刺激—机体—反应（SOR）理论为框架，构建三者之间的理论模型。研究发现，视障者数字媒介可及性较高，但服务可及性及技术可及性仍需加强。媒介可及性正向促进视障者数字媒介使用态度，自尊与主观社会支持在其中起中介作用。本文认为技术不能孤立地发挥作用，媒介、个体、社会三者密不可分，因此真正的“可及”是在视障者主动选择、市场快速响应、国家创造机遇基础上的“可获取”。视障者媒介使用研究也应当弱化其生物性，突出社会性，以更好地“呈现”而非“代理”这一群体。

关键词：信息无障碍视障群体媒介可及媒介歧视自尊

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飞轮储能辅助火电机组一次调频过程仿真分析

储能科学与技术 2021年第5期10卷 1679-1686页

作者：何林轩李文艳华北电力大学能源动力与机械工程学院北京102206

为了分析飞轮储能辅助火电机组一次调频的效果,建立两区域电网模型,利用MATLAB/Simulink软件分析在阶跃扰动和连续扰动情况下有无飞轮储能参与时系统的调频效果及调频资源的出力情况。仿真结果表明,与火电机组单独调频相比,由于飞轮储... 详细信息

为了分析飞轮储能辅助火电机组一次调频的效果,建立两区域电网模型,利用MATLAB/Simulink软件分析在阶跃扰动和连续扰动情况下有无飞轮储能参与时系统的调频效果及调频资源的出力情况。仿真结果表明,与火电机组单独调频相比,由于飞轮储能能够快速响应频率偏差信号,调频过程中系统频率的最大暂态偏差得以减少,飞轮储能的参与使系统在一定的阶跃扰动条件下的稳态频率偏差减少了7.58×10^(−5)p.u.,在一定的连续扰动条件下两区域最大频率偏差分别减少了2.02×10^(−4)p.u.和1.47×10^(−4)p.u.,且交换功率变化最大值在两种扰动条件下分别减少了2.84×10^(−4)p.u.和1.52×10^(−3)p.u.;由于飞轮储能承担了一部分调频任务,使得在阶跃扰动条件下火电机组的稳态输出功率变化量减少了1.517×10^(−3)p.u.,在连续扰动条件下的整个调频过程中火电机组的出力变化范围得以减少。综合分析表明,在相同的仿真条件下,采用飞轮储能辅助一次调频可以减少电力系统频率偏差变化量和联络线上交换功率的变化范围并且减轻火电机组调频负担,减少火电机组输出功率的变化范围,延长机组寿命。

关键词：飞轮储能火电机组一次调频荷电状态